The present invention relates to a closure system for a disposable absorbent article, particularly multifunctional closure systems attachable to the waistband portions of the disposable absorbent article.
In the field of disposable absorbent articles, typically disposable diapers and adult incontinent articles, closure systems are provided which generally are formed using pressure sensitive adhesive fastening tabs or mechanical fastening tabs. These tabs are generally attached to the disposable absorbent article at corner portions at at least one end of the article, e.g., a diaper. The typical fastening tabs have one end which is permanently bonded to the absorbent article and a second free end which is available for the user to removably attach to the opposing end of the article to effect closure. The opposing end of the absorbent article typically is provided with a mating attachment surface. In the case of pressure sensitive adhesive fastening tabs, the mating attachment surface typically is a reinforcement film or other material which is applied to the inside or outside face of the outer liquid impermeable layer of the disposable absorbent article. In the case of a mechanical fastening tab, the mating attachment surface is a loop fastening material which must be placed on the outside face of the liquid impermeable outer cover layer of the disposable absorbent article. In either case, the mating attachment surface is typically provided by applying a separate discrete element to the absorbent article. This could be a pressure sensitive adhesive element or a non-adhesive coated element bonded by other means such as hot melt adhesive or thermal welding. In certain extreme cases, the entire outer face of the disposable absorbent article can be provided with a suitable mating attachment surface for the fastening tab second free end, however this can be excessively costly. The fastening tab itself is also applied as a separate and discrete element to the corner of the disposable absorbent article, generally at the back end region. Generally, this permanent attachment of the fastening tab is made by a pressure sensitive adhesive applied at one end of the fastening tab with the other second end of the fastening tab provided with a suitable pressure sensitive adhesive or mechanical fastening element for releasable attachment and closure of the absorbent article. The fastening tab can be applied as a separate piece cut from a roll which can be laminated with other suitable materials, such as a release tape, during the manufacture of the diaper. Alternatively, the fastening tab can be provided with other suitable components in a pre-laminate form which also is cut from a continuous roll. These closure systems are highly effective but can be complicated, particularly when they are laminated on the diaper line and/or additional functionality is incorporated into the fastening tab, such as elasticity.
It has also been proposed in the patent literature that suitable belt means could be provided with attachment elements at the opposing ends of the belt to provide a closure system for use with a disposable absorbent article. Belts can address some of the issues regarding separate tab fasteners as some only require the use of a single laminate or the like which can be securely or releasably attached to a diaper absorbent pad or the like. However the use of two interconnecting belts have also been proposed. In U.S. Pat. Nos. 3,847,702 and 3,561,446, an inextensible belt material is provided both to the front and back ends of a disposable diaper. Each belt extends across the full width of the diaper and both belts are provided at the terminal ends with a pressure sensitive adhesive region which adhesive is covered until use with a release tape. When the diaper is closed, one belt is attached to some portion of the second belt at the opposite end of the diaper, and the adhesive on the terminal ends of the second belt is generally attached to the diaper on the diaper face opposite that provided with the first belt. These belts prevent inelastic deformation of the waistband region of the diaper during use. However, this two-belt system would be similar in manufacturing complexity to the use of tab fasteners.
French Pat. Nos. 2,586,558, 2,725,879, and PCT Publ. No. 94/26224 teach the use of only one inextensible belt which single belt can be attached to the front or rear ends of the diaper, either permanently or by refastenable mechanical fastening elements. When the diaper is refastenably attached to the belt, the belt can be reused repeatedly. In these patent documents, the belt generally wraps around the wearer and secures to itself with the diaper being releasably attached to the belt at least at one end of the diaper, and either releasably or permanently attached to the belt at the opposing end of the diaper. A similar approach is proposed in U.S. Pat. No. 4,964,860, and PCT application No. 91/08725 where a reusable belt with mechanical fastening elements is used with a disposable diaper provided with mating mechanical fastening elements. These belts can be relatively easy to incorporate onto a diaper but lack the ease of use of a fastener tab closure system for the end user.
In EP Appln. No. 528282, a permanent integral waistband is provided on a diaper which waistband could be stretchable. The waistband is on one end of the diaper and wraps around the wearer's waist and attaches to itself forming a belt. Both the waistband and the front portion of the diaper are provided with suitable interengagable attachment elements 44 and 50 which could be any variety of attachment means including pressure sensitive adhesives, cohesive adhesives, and mechanical fasteners. The front portion of the diaper would attach to the waistband portion. This patent attempts to combine some of the benefits of a single belted system with those of a tab fastening closure system.
In U.S. Pat. No. 5,593,401, a bridging type element is provided at one end region of a diaper as a separate element to which may be attached two conventional fastening tabs at either end. The bridge strip has a secured side and an unattached side and is generally described as being elasticized. This bridge strip would require a separate attachment step and associated apparatus in order to be integrated into the disclosed conventional diaper constructions. This is similar to the above two belt systems but is more complicated in terms of its construction and manufacture.
Elasticized waist elements which may have attached fastening tabs that then releasably attach to a front panel portion of a diaper are disclosed in U.S. Pat. No. 4,998,929, and PCT Publ. Nos. WO 96/32083, and WO 95/22951. An elastic type belt element which wraps around the entire waist of the wearer and which is provided with inter-engaging mechanical fastening elements at its terminal ends is disclosed in U.S. Pat. No. 5,607,416. In all the above patent documents, there is a separate and distinct elastic element with the terminal edges generally including an attachment element such as a pressure sensitive adhesive or a mechanical fastening element which attaches to the elastic belt as per U.S. Pat. No. 5,607,416 or to a suitable attachment mechanism on the other end portion of the diaper or like disposable absorbent article.
The use of two or one belt closure systems that wrap around one end of a diaper or the entire waist of the wearer, respectively, are desirable from a number of perspectives. The belt can be used with the closure system in a manner that provides other functionality such as elasticity or inextensibility that is actively integrated with the closure system. However, the means proposed for providing these belt and closure elements generally requires a number of separate attachment steps on the manufacturer's line.
The invention is directed at addressing the manufacturing complexities of multicomponent closure systems by enabling the provision of an effective closure system by a single attachment step which can also provide additional desired functionality such as inextensible belt elements, extensible belts or bands, elasticity, and the like. The invention is also directed at a method of providing a diaper closure system and optionally a belt system on a diaper line by the use of a single closure system laminate.